外源水杨酸对盐胁迫下蕹菜种子萌发及幼苗生长的影响

用不同浓度的水杨酸(SA)(0.15、0.25、0.50、1.00、1.50、2.00 mmol/L)处理0.9% NaCl胁迫的蕹菜种子,测量种子萌发指标以及幼苗生长指标,以期研究盐胁迫条件下,不同浓度SA对蕹菜种子萌发及幼苗生长的影响。试验结果表明,0.9%NaCl胁迫对蕹菜种子发芽率的影响不明显,但显著降低发芽势、发芽指数和活力指数,明显抑制幼苗的芽、根以及侧根生长。0.15 mmol/L SA能缓解NaCl盐胁迫作用,对蕹菜种子萌发和幼苗生长的伤害,提高其抗盐能力;而在0.25~2.00 mmol/L SA浓度范围内,随SA浓度的增加,蕹菜种子萌发和幼苗生长受抑制程度加重。     

SA对盐胁迫下萝卜种子萌发和幼苗生长的影响

为了探讨外源水杨酸(SA)对盐胁迫下3种萝卜(‘花樱萝卜’‘西春伏萝卜3号’‘水萝卜’)种子萌发和幼苗生长的影响,采用不同浓度SA处理150 mmol·L^-1NaCl胁迫下的萝卜种子,测量种子萌发、幼苗生长及生理指标。结果表明:(1)NaCl胁迫显著抑制了萝卜种子的萌发和幼苗的生长;(2)不同浓度SA处理下,1.5 mmol·L^-1的SA处理(T3组)对盐胁迫下萝卜种子萌发和幼苗生长缓解效果最好,‘西春伏萝卜3号’在该处理下比其他处理的发芽率高6.67-14.45个百分点,‘花樱萝卜’T3组发芽率高于其他组7.78-26.67个百分点,‘水萝卜’T3组发芽率最高,但与其他处理相差不大。研究发现,外源SA在一定程度上能缓解盐胁迫对萝卜种子萌发和幼苗生长抑制作用,其中以1.5 mmol·L^-1的SA处理缓解效应最好,且缓解效应在不同萝卜品种间存在差异。     

水杨酸对盐胁迫下中国石竹种子萌发及幼苗生长的影响

以中国石竹种子为试验材料,在150 mmol/L NaCl胁迫处理下,试验不同浓度的外源水杨酸(SA)对中国石竹种子萌发及幼苗生长的影响。结果表明:盐胁迫下,1.5 mmol/L的水杨酸预处理的中国石竹种子具有较高的发芽势、发芽率、发芽指数、活力指数。同时,1.5 mmol/L处理的中国石竹幼苗具有较长的胚芽、胚根长度和较高的干重。说明一定浓度的外源SA,可有效促进盐胁迫下中国石竹种子萌发和幼苗生长。     

外源水杨酸对盐胁迫下凤仙花种子萌发特性的影响

以凤仙花成熟种子为试材,研究比较了水杨酸(SA)处理对盐胁迫下凤仙花种子的发芽势、发芽率、发芽指数等萌发指标,胚根长、下胚轴长及幼苗的可溶性糖、可溶性蛋白质与丙二醛(MDA)含量等的影响.结果表明:SA处理后种子萌发指标和幼苗生理指标均有不同变化.其中SA浓度为50 mg/L时,萌发指标均达到最大值;幼苗MDA含量为最小值.50 mg/L的SA能够有效的缓解盐胁迫对凤仙花种子及幼苗产生的伤害,提高种子及幼苗的抗盐性.     

水杨酸对盐胁迫下辣椒种子萌发及幼苗生长的影响

该试验对NaCl胁迫下生长的辣椒幼苗进行水杨酸(SA)处理,分别采用浸种法和水培法在种子萌发期和幼苗期进行研究,以期研究外源SA对盐胁迫下作物生长的缓解作用,降低盐胁迫对作物的伤害,提高中、轻度盐碱地的利用率。结果表明:盐胁迫会抑制辣椒种子的萌发和幼苗生长,当SA浓度为0.15 mmol·L~(-1)时,种子的发芽势、发芽率等最高,缓解盐胁迫的效果最佳;利用外源水杨酸对盐胁迫下的辣椒苗进行生长调控,叶片的净光合速率(Pn)、气孔导度(Gs)显著降低,细胞间隙CO_2浓度(Ci)持续升高,表明SA可以缓解盐胁迫对植物的抑制作用,提高叶片光合作用的效率,同时与NaCl处理相比,叶绿素含量在第3、6、9天分别增加51%、34%、40%,这表明SA可以缓解盐胁迫对辣椒幼苗的生长抑制,促进叶片叶绿素的合成,保护其光合作用,维持植物的正常生长。     

水杨酸对盐胁迫下番茄幼苗生理指标的影响

以番茄品种“合作908”和“奇达利”为试材,研究了不同浓度(0.1、0.5、1、2、4 mmol/L)水杨酸(SA)诱导盐胁迫下对番茄幼苗生理指标的影响.结果表明:SA可有效抑制叶绿素含量的减少;增强叶片过氧化物酶( POD)、过氧化氢酶(CAT)的活性;降低膜脂过氧化产物丙二醛(MDA)含量和质膜透性,缓解了盐胁迫对幼苗生长的抑制.SA的最佳诱导浓度为1mmol/L.     

罗布麻和大叶白麻种子萌发及幼苗生长耐盐性研究

以罗布麻(Apocynum venetum Linn.)和大叶白麻(Poacynum hendersonii(Hook.f.)Woodson)种子为试材,研究了0(CK)、50、100、200、400、600mmol/L NaCl 6个盐浓度胁迫下种子发芽率及胚根、胚芽生长。同时,为揭示罗布麻幼苗耐盐特性,采用砂培法培养植株,分析了不同盐浓度胁迫下罗布麻幼苗不同部位生物量的变化。结果表明:盐胁迫可抑制2种罗布麻种子发芽率及胚根、胚芽生长,2种罗布麻种子萌发的耐盐临界值为400mmol/L左右,胚根生长的耐盐临界值为100mmol/L NaCl;600mmol/L NaCl可完全抑制罗布麻和大叶白麻种子的萌发,但解除盐胁迫复水后,2种罗布麻种子发芽率及胚根、胚芽生长恢复至对照水平;盐胁迫对种子发芽率、胚根、胚芽生长及幼苗不同器官生物量的影响表明,大叶白麻种子萌发和幼苗生长阶段较罗布麻耐胁迫,通过对2种罗布麻生境分析,认为这是与它们的生境相适应的。罗布麻种子萌发和幼苗生长耐盐性研究对盐碱地上罗布麻的人工栽培有重要指导意义。     

外源水杨酸和甜菜碱对NaCl胁迫下茶花凤仙种子萌发的影响

以茶花凤仙(Impatiens balsamena)种子为试材,采用双层滤纸法,研究了100 mmol·L^-1NaCl胁迫条件下,外源SA(0.5、1.0、1.5、2.0 mmol·L^-1)和GB(0.4、0.8、1.2、1.6 mmol·L^-1)浸种预处理对茶花凤仙种子萌发及幼苗生长的影响,以期明确茶花凤仙种子萌发期2种外源物质对NaCl胁迫的缓解效应,降低NaCl胁迫对茶花凤仙的伤害。结果表明:NaCl胁迫显著抑制了茶花凤仙种子的萌发,发芽率、发芽势、发芽指数、活力指数、胚芽长、胚根长和苗鲜质量均显著下降,平均发芽时间显著延长;1.5 mmol·L^-1SA和0.8、1.2 mmol·L^-1GB对NaCl胁迫下茶花凤仙种子萌发和幼苗生长具有明显促进作用,而SA和GB浓度过高或过低则对NaCl胁迫的缓解效应下降,甚至加重盐害。利用隶属函数综合评价得出,100 mmol·L^-1NaCl胁迫下,1.5 mmol·L^-1SA和0.8 mmol·L^-1GB对茶花凤仙种子萌发及幼苗生长的综合调控效果较好,且0.8 mmol·L^-1GB对NaCl胁迫的缓解效果优于1.5 mmol·L^-1SA。     

水杨酸对盐胁迫下苦瓜种子萌发及幼苗生长的影响

为探究水杨酸(SA)对苦瓜盐害的缓解作用,以苦瓜品种良苦1号为试材,采用拌种和叶面喷施的方法,研究不同浓度(0.001、0.01、0.1、1.0 mmol·L^-1)SA处理对150 mmol·L^-1NaCl胁迫下苦瓜种子萌发和幼苗生长的影响。结果表明,0.01 mmol·L^-1SA处理显著提高了盐胁迫下苦瓜种子的发芽率、发芽势、发芽指数、活力指数及幼苗的株高、叶面积、根长、鲜质量、干质量。0.1 mmol·L^-1SA处理显著提高了苦瓜种子的发芽率、发芽势及幼苗的叶面积、鲜质量、干质量,对种子的发芽指数、活力指数及幼苗的株高、根长无显著影响。0.01 mmol·L^-1SA处理显著提高了苦瓜幼苗抗氧化酶(SOD、POD、CAT)的活性及脯氨酸、可溶性糖的含量,显著降低了丙二醛的含量。0.1 mmol·L^-1SA处理显著提高了苦瓜幼苗POD的活性及脯氨酸、可溶性糖的含量,对SOD、CAT的活性及丙二醛的含量无显著影响。综上,施用一定浓度外源SA对苦瓜盐害具有缓解...     

ALA对胁迫下西瓜种子萌发的促进效应

盐渍胁迫往往抑制植物种子萌发与幼苗生长.如何促进盐胁迫下种子萌发是盐渍土地区作物栽培的重要技术环节.以西瓜为材料,研究了不同浓度NaCl处理对种子萌发的影响,发现在125 mmol/L NaCl处理下添加15～30mg/L外源5-氨基乙酰丙酸(ALA)可以明显缓解盐胁迫对种子萌发和幼苗生长的抑制效应,并提高幼苗超氧化物歧化酶(SOD)、抗坏血酸过氧化物酶(APX)以及过氧化物酶(POD)活性,降低丙二醛(MDA)含量和脂氧合酶(LOX)活性.此外,利用POD活性抑制抗坏血酸(AsA)处理,则可完全抑制ALA对种子发芽的促进效应.以上结果表明,外源ALA能够促进盐胁迫下西瓜种子萌发,并且可能与ALA诱导抗氧化酶,特别是POD活性的提高有关.     

Effects of radiation from 188Re on smooth muscle cell proliferation

AIM: Although endovascular radiotherapy inhibits neointimal hyperplasia, the exact alterations induced by β-particles irradiation remain to be elucidated. The objective of this study was to investigate the ability and the cellular mechanism of local β^-particles emission from ¹⁸⁸Re to inhibit vascular smooth muscle cells (SMCs). METHODS: The SMCs in vitro were irradiated by ¹⁸⁸Re with single doses of 2.6 Gy-25.8 Gy. The effects of β-particles on SMCs, such as effective irradiate doses, the period of inhibition for SMCs proliferation, the changes of cell proliferation rate and DNA synthesis rate, cell cycle progression and related gene expression, were investigated by cell count, [³H]-TdR incorporation, cell cycle progression analysis, cell viability and immunocytochemistry, respectivecy. RESULTS: β-particles irradiation with dose of 5.2 Gy could inhibit significantly SMCs proliferation. At dose of 20.6 Gy DNA synthesis inhibitory rate was 92%, SMCs proliferation rate was only 3%. Renoval of ¹⁸⁸Re did not abolish the inhibitory effects of β-particles on SMCs proliferation. The expression of P53 was up regulation and PCNA was down regulation after irradiation. CONCLUSION: β-particles from ¹⁸⁸ Re was significantly effective and permanent in inhibiting SMCs proliferation, and inhibitory effect was in dose-dependet manner ED50was 5 Gy, the best dose to inhibit SMCs proliferation was 20 Gy. β-particles irradiation induced SMCs to occur G₀/G₁ arrest, damaged the ability of SMCs reproliferation and led to cell clonogenic death. P53 and PCNA had regulatiory effects on SMCs proliferation after β-particles irradiation.     

多效唑对猕猴桃离体试管苗生长及内源激素的影响

多效唑（ＰＰ３３３）处理猕猴桃试管苗，降低了其生长强度；植株体内的ＧＡ３、ＩＡＡ和ＺＴ含量下降，ＡＢＡ的含量上升，乙烯释放率增加；并且能降低外源的ＧＡ３和ＩＡＡ促进生长的作用，而外源的ＧＡ３和ＩＡＡ又能不同程度地逆转多效唑的抑制作用，使植株恢复生长。     

Proteomic analysis between pathological scars and normal skin

AIM: To investigate and screen the sensitive proteins in the formation mechanism of pathological scars by comparing the results of differential proteomic analysis between pathological scars and normal skin.METHODS: Two-dimensional gel electrophoresis was used to detect the protein expression profiles in 8 keloid patients, 8 hypertrophic scar patients and 3 matched normal skin patients.The proteins that showed differential expression of over 4-fold change were cut and analyzed by MALDI-TOF/TOF mass spectrometry.RESULTS: A two-dimensional protein profiling comparison between pathological scars and normal skin was successfully established.On average, 2 978 spots in keloid, 2 975 spots in hypertrophic scar and 3 053 spots in normal skin were identified using gel analysis software.Compared with normal skin, there were totally 36 differentially-expressed proteins in keloid and hypertrophic scar identified from the spots of over 4-fold change, including 16 proteins in both keloid and hypertrophic scar (8 up-regulated and 8 down-regulated), 11 only in keloid (9 up-regulated and 2 down-regulated) and 9 only in hypertrophic scar (4 up-regulated and 5 down-regulated).CONCLUSION: Proteomic analysis can identify the proteins with variance of pathological scars versus normal skin, thus providing probable new clues to reveal the formation mechanism of pathological scars.     

Coupling past management practice and historic landscape change on John F. Kennedy Space Center,Florida

Historic landcover dynamics in a scrubby flatwoods (Tel-4) and scrub landscape (Happy Creek) on John F. Kennedy Space Center were measured using aerial images from 1943, 1951, 1958, 1969, 1979, and 1989. Landcover categories were mapped, digitized, geometrically registered, and overlaid in ARC/INFO. Both study sites have been influenced by various land use histories, including periods of range management, fire suppression, and fire management. Several analyses were performed to help understand the effects of past land management on the amount and spatial distribution of landcover within the study sites. A chi-squared analysis showed a significant difference between the frequency of landcover occurrence and management period. Markov chain models were used to project observed changes over a 100-year period; these showed current management practices being effective at Tel-4 (restoring historic landscape structure) and much less effective at Happy Creek. Documenting impacts of past management regimes on landcover has provided important insight into current landscape composition and will provide the basis for improving land management on Kennedy Space Center and elsewhere.     

XBP-01 accelerated apoptosis induced by oxidized low density lipoprotein in vascular smooth muscle cells

AIM: Previous studies performed with XBP-01 in vitro indicated that XBP-01 could inhibit vascular smooth muscle cells from being transformed into foam cell and could eliminate the atherosclerotic plaque in C57BL/6J mouse. This experiment is to investigate its mechanism of eliminating plaques in vitro. METHODS: The cultured porcine artery smooth muscle cells incubated with XBP-01 of 0.1 mg/L for 24 h after preincubated with oxidized low density lipoprotein of 15 mg/L for 72 h in vitro. The samples were analyzed by fluorescence microscope, confocal microscope system and flow cytometry. RESULTS: Apoptosis was triggered by being incubated with oxidized low density lipoprotein and this process was accelerated additionally by being incubated with XBP-01. CONCLUSION: XBP-01 can be effective in eliminating atherosclerotic plaque by accelerating the process in which oxidized low density lipoprotein induced smooth muscle cell apoptosis.     

The effect of exposure on landscape scale soil surface temperatures and species distribution models

Species distribution models (SDMs) often use elevation as a surrogate for temperature or utilise elevation sensitive interpolations from weather stations. These methods may be unsuitable at the landscape scale, especially where there are sparse weather stations, dramatic variations in exposure or low elevational ranges. The goal of this study was to determine whether radiation, moisture or a novel estimate of exposure could improve temperature estimates and SDMs for vegetation on the Illawarra Escarpment, near Sydney, Australia. Forty temperature sensors were placed on the soil surface of an approximately 12,000 ha study site between November 2004 and August 2006. Linear regression was used to determine the relationship with environmental factors. Elevation was correlated more with moderate temperatures (winter maximums, summer minimums, spring and autumn averages) than extreme temperatures (summer maximums, winter minimums). The correlation (r ²) between temperature and environmental factors was improved by up to 0.38 by incorporating exposure, moisture and radiation in the regressions. Summer maximums and winter minimums were predominately determined by exposure to the NW and coastal influences respectively, while exposure to the NE and SW was important during other seasons. These directions correspond with the winds that are most influential in the study area. The improved temperature estimates were used in Generalised Additive Models for 37 plant species. The deviance explained by most models was increased relative to elevation, especially for moist rainforest species. It was concluded that improving the accuracy of seasonal temperature estimates could improve our ability to explain the patchy distribution of many species. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Expression and significance of c-IAP2 and GAS1 in Hodgkin's lymphoma and anaplastic large cell lymphoma

AIM: To detect the expression of cytoplasmic inhibitor of apoptosis protein 2 (c-IAP2) and growth arrest-specific gene 1 (GAS1) in Hodgkin's lymphoma (HL) and anaplastic large cell lymphoma (ALCL) and to investigate the role of two genes in the pathogenesis of HL and ALCL.METHODS: HE staining, the antibodies CD30, CD15, CD45RO and CD20 were used to screen the cases of HL and ALCL from 288 cases of lymphoma. The clarified HL and ALCL were subjected for immunohistochemical staining by SP and ABC methods to analyze the expression of c-IAP2 and GAS1. RESULTS: ①The positive rate of c-IAP2 in HL was 25/26(96.1%) while that in ALCL was 6/19(31.6%), there presented statistic significance between HL and ALCL groups(P<0.05), meanwhile the positive rate of GAS1 showed statistic significance between HL and ALCL groups(P<0.05). ②Two cases were showed to be a mixed type combined with large tumor cells of HL and relatively smaller tumor cells of ALCL.CONCLUSION: ①The different expression of c-IAP2 and GAS1 in HL and ALCL implied a different mechanism of oncogenesis and the different defects in the pathway of signal transduction of apoptosis in HL and ALCL;②Few cases showed an overlap and a likely transitional state between HL and ALCL; ③The different expressing manner of GAS1 and c-IAP2 in HL and ALCL implied the potential marks for the differential dignosis of two kinds of lymphoma.     

Effects of patch attributes, barriers, and distance between patches on the distribution of a rock-dwelling rodent (Lagidium viscacia)

We tested whether size of habitat patches and distance between patches are sufficient to predict the distribution of the mountain vizcacha Lagidium viscacia a large, rock-dwelling rodent of the Patagonian steppe Argentina, or whether information on other patch and landscape characteristics also is required. A logistic regression model including the distance between rock crevices and depth of crevices, distance between a patch and the nearest occupied patch, and whether or not there was a river separating it from the nearest occupied patch was a better predictor of patch occupancy by mountain vizcachas than was a model based only on patch size and distance between patches. Our results indicate that a simple metapopulation analysis based on size of habitat patches and distance between patches may not provide an accurate representation of regional population dynamics if patches vary in habitat quality independently of patch size and features in the matrix alter connectivity. This revised version was published online in August 2006 with corrections to the Cover Date.     

Inhibitory β-adrenergic receptor in heart

β₃-adrenergic receptor is the third subtype of β-adrenergic receptors. The genetic structure and pharmacological property of β₃-adrenergic receptor are markedly distinguished from β₁-and β₂-adrenergic receptor subtypes. Recently studies show that myocardial β₃-adrenergic receptor mediates negative inotropic effect through Gi-protein/NO/cGMP pathway, the expression of β₃-adrenergic receptor and negative inotropic effect mediated by β₃-adrenergic receptor are increased in heart failure. However, because of the low expression of β₃-adrenergic receptor in the heart, the actual pathophysiological significance of β₃-adrenergic receptor remains unknown.